The invention relates to an arrangement of a brake disc on a wheel hub.
To connect a brake disc to a wheel hub and transmit a braking torque which arises during braking to the wheel hub and hence to a connected vehicle wheel, intermeshing tooth-shaped positive engagement means are known, consisting of support elements provided on the inner circumference of the brake disc and of drivers disposed on the outer circumference of the wheel hub and corresponding to said support elements to give an anti-twist lock.
To secure the brake disc axially on the wheel hub, there are known support elements which are designed as leaf springs and are each, on the one hand, screw-fastened to a driver and, on the other hand, rest with a spring pressure against the adjacent support elements of the brake disc by means of their wings, which extend on both sides of the bolt.
Disposed in the area in which the brake disc is connected to the wheel hub, there is generally a magnet wheel, which is employed as a functional component of an anti-lock system (ABS). Here, the magnet wheel, which is in operative connection with a sensor, is fastened to the wheel hub in a manner secure against twisting.
This can be accomplished by bolting, for example, as known from German Patent Document No. DE 10 2004 034 361 B3.
Other approaches to fastening include fixing the magnet wheel in a hole in the wheel hub or directly on the latter by means of a pressed joint, for example.
However, this joint is problematic since differences in the thermal expansion of the magnet wheel and the wheel hub and/or brake disc mean that there is a risk of loosening, severely impairing the ability to function of the anti-lock system overall. To compensate for these differences in thermal expansion, German Patent Document No. DE 10 2005 056 063 A1, for example, proposes to employ a spring sleeve.
Whatever the case may be, the mounting of the magnet wheel close to the brake disc is problematic, especially in the case of a neckless brake disc of the type in question, owing to the frictional heat which arises during braking, and this is an obstacle to permanently reliable operation of the system.
It is the underlying object of the invention to develop an arrangement of the type in question in such a way that the magnet wheel can be fastened without additional effort on assembly and that the service life of the magnet wheel connection is improved.
This object is achieved by an arrangement which meets the requirements set in all respects. In particular, the magnet wheel's ability to function is assured, even in extremely difficult operating conditions, i.e. high thermal loads, because there is always a reliable connection between the magnet wheel and the wheel hub or brake disc.
Since the components forming an arrangement according to the invention are, in their totality, a system relevant to safety, said improvement is of particular significance.
However, the invention is also distinguished from the prior art in a special way in economic terms.
Thus, the first point to be emphasized is that now no special measures are required for fastening the magnet wheel.
There is no need either to introduce additional threaded holes into the wheel hub, as is the case with the prior art cited, or to make provision in terms of production engineering in order to press together the magnet wheel and the corresponding component, for example.
This naturally leads to a significant reduction in costs, and, what is more, the simplified way in which the magnet wheel can be removed also contributes to this result.
To achieve this, all that is required is to undo the corresponding connecting element, i.e. the bolt, by which the securing element, i.e. the leaf spring mentioned, is held on the corresponding driver of the wheel hub, in order to replace a damaged magnet wheel, for example.
In addition, the magnet wheel can be produced without additional production measures. All that is required is to fit the attachment parts, which are preferably designed as attachment tabs and are expediently integrally formed. In this case, all that is necessary is appropriate forming work, of the type that usually has to be carried out in any case for the purpose of forming the magnet wheel.
According to an advantageous development of the invention, the drivers associated with the attachment tabs have recesses, in which the tabs rest, and the shape and dimensions of the recesses are matched at least in a certain section or certain sections to those of the respective attachment tabs.
It is thereby possible to achieve anti-twist locking of the magnet wheel by forming, while axial retention is accomplished through the clamping provided by the leaf springs, which partially overlap the attachment tabs.
According to another concept forming part of the invention, the attachment parts, preferably said attachment tabs, are angled approximately in an L shape and disposed on the outer rim of the magnet wheel, with a small number disposed at angular intervals equal to the intervals at which the wheel hub drivers, in which the attachment tabs rest, are positioned being sufficient in principle.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of one or more preferred embodiments when considered in conjunction with the accompanying drawings.